Giacomo Giannini

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In order to reduce magnetic-acoustic noise emitted by asynchronous traction motors fed by inverter, a new kind of space vector modulation techniques have been developed. By using these, called mixed random modulation techniques (MRMT), a better ldquosound qualityrdquo of emitted noise is reached. They act modifying both SVM pulse position and SVM switching(More)
IGBT series-connected power switching circuit is presented. Voltage balance on IGBT's is ensured by means of a simple auxiliary circuit applied directly on the high power inverter used in hard switching applications. Analysis in terms of dissipated energy, collector overvoltage and switching frequencies, comparing performances of a single high voltage IGBT(More)
A new optimization strategy for driver circuits in high power-high voltage IGBTs is proposed. Main features of such an approach are the reduction of the switching losses and active control of the device overvoltage. To confirm the proposed approach, an auxiliary circuit has been realized and used to equip an industrial driver, then experimental tests have(More)
The supply catenary lines for electric vehicles, and specifically for urban streetcars, may be subject to a series of discontinuities which could determine the power switch-off of the traction converter, due to protections intervention. The proposed system, based on a two-quadrant DC/DC converter, a supercapacitors bank and a suitable control system, can(More)
The aim of this work is the study and implementation of mixed random modulation techniques for the reduction of magnetic-acoustic noise in asynchronous motors for railway traction, fed by inverter. The current harmonics generated by PWM modulation cause an increase in the magnetic noise of the motor. The switching frequency is relatively low for this kind(More)
A high-efficiency high-frequency link inverter design with bi-directional power flow, using a zero-voltage-switching (ZVS) technique is proposed. The considered configuration includes a HF full-bridge inverter, a HF transformer, a 3-phase cycloconverter; Required bidirectional switches have been composed by anti-series IGBT connection. Main advantages of(More)
Relationship between choices of power semiconductor devices and converter topologies are discussed, for multisystem locos. Advantages of dual-stage converter, associated to press-pack 4.5 kV IGBT are presented. Ansaldobreda phase-assembly for heavy railway is presented, as well as performances of power converter of E403 loco
The driving improvement in terms of IGBT switching losses reduction is accompanied by a significant increase of EMC noise problems. In this paper, the authors focused their attention on the electromagnetic noise radiated by the high voltage high power IGBT modules during the inductive turn-on. The noise variation and the dependence of each IGBT commutation(More)
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